Abrasive unit



July 21, 1959 Filed Feb. 19, 1958 J. 5. KOZACKA 2,895,267

ABRASIVE UNIT 2 Sheets-Sheet 1 INVENTOR.

July 21, 1959 5, KQZACKA 2,895,267

ABRASIVE UNIT Filed Feb. 19, 1958 2 Sheets-Sheet 2 INVENTOR.

United States Patent M 2,895,267 ABRASIVE UNIT Joseph S. Kozacka,Chicago, Ill., assignor to Ski] Corporation, Chicago, IlL, a corporationof Delaware Application February 19, 1958, Serial No. 716,118

' 6 Claims. (Cl. 51 -194) The present invention is directed to a new andimproved abrasive unit of the type particularly adapted for use inleather working such as carried out in the manufacture of shoes.

In shoe manufacture and repair work, a series of cylindrical abrasiveunits are mounted on a single rotatable shaft in spaced end-to-endrelation. Normally, the abrasive properties of the different units willvary from coarse to fine to provide a series of units capable ofcompleting the different operational stages of leather shaping andfinishing. The mounting of a plurality of abrasive units on a singleshaft not only allows savings in the use of a single power source anddrive connection for rotating the shaft, but also provides forefiiciency in leather shaping operations by allowing the operator toquickly move from one abrasive unit to another for variable abrasiveaction. The mounting of a plurality of spaced abrasive units on a singleshaft is also advantageous even if the individual abrasive units do notvary in abrasive action, as a'plurality of operators can utilize thesame power source and equipment in carrying out leather shapingoperations.

The abrasive material generally used in the past is in the form offlexible paper such as sandpaper, emery paper, garnet paper, aluminumoxide paper, and the like. Rapid deterioration of the abrading orscoring surface of such material is prevalent resulting in substantialeconomic losses due to the necessity for replacing the material. Eventhough sandpaper and related articles are relatively inexpensive, theyconstitute a distinct economic disadvantage insofar as the overallfinishing processing is concerned. Such abrading and scoring articlesare relatively low in efiiciency, particularly when applied to surfacefinishing of relatively tough or hard materials.

As disclosed in co-pending applications, Serial No. 676,766, filedAugust 7, 1957, and Serial No. 676,774, filed August 7, 1957, animproved form of abrasive ele ment is now available wherein the workingsurface thereof is coated with an improved abrasive such as sinteredtungsten carbide. The new abrasive material may .be readily applied to arigid base such as a section of tubing to supply an abrasive elementcapable of longlife, efiicient operation. With the mounting of theabrasive material on a rigid tube member the same can be concentricallymounted about a shaft for rotation therewith in the forming of anassembly of a plurality of such units mounted on a single shaft asdescribed above. It will be appreciated however, that if tubularabrasive elements of this type are mounted on a single shaft in spacedrelation therealong, it would be necessary to thread the elements ontothe shaft for fixing thereto in the particular order desired. Readyrearrangement of the various units would be diflicult in the respectthat it would be necessary to remove the endmost units in order to gainaccess to an intermediate unit for rearrangement of the same along theshaft or for replacement of various parts thereof. In certain instances,the units 2,895,267 Patented July '21, 1959 removed in order to gainaccess to an intermediate unit would not need maintenance or replacementof parts thereof and the time and effort consumed in dismounting andsubsequently remounting these units would materially add to the overalltime during which the entire assembly would be out of operation.

It is an object of the present invention to provide a new and improvedabrasive unit utilizing a rigid abrasive element for mountingconcentrically relative to a rotatable shaft or the like, the abrasiveelement being driven by mounting members constituting a part of the unitand being capable of providing extended and efiicient abrasive actionfor material finishnig processing.

Another object of the present invention is to provide a new and improvedabrasive unit incorporating therein certain structural features allowingready mounting or replacement of the abrasive element thereof withoutdisturbing adjacent units mounted on a common shaft.

Still a further object is to provide a new and improved abrasive unitassembly of uncomplicated structural arrangement, the assembly includingabrasive element mounting features allowing for quick and efficientabrasive element mounting or replacement without actual removal of anyportion of the unit from the shaft on which it is mounted with theexception of the abrasive element to be replaced.

Still another object taken in conjunction with the foregoing is toprovide an improved form of abrasive unit in which the abrasive elementthereof is not only readily mountable 0r replaceable without dismountingthe permanent mounting elements of the unit from the shafts, but thepermanent mounting elements of the unit are adapted to efliciently mountabrasive elements of variable length, the relative location of themounting elements being readily varied while retained on the shaft toaccommodate different lengths of abrasive elements.

Other objects not specifically set forth will become apparent from thefollowing detailed description made in conjunction with the drawingswherein:

Fig. 1 is a fragmentary perspective of a typical installation of aplurality of abrasive units of the present invention;

Fig. '2 is an enlarged perspective of the removable semi-cylindricalabrasive element sections of the unit of the present invention;

Fig. 3 is a fragmentary, partly sectioned elevation of the asembledunit;

Fig. 4 is a longitudinal section of the unit;

Figs. 5 and 6 are side and front elevational views, respectively, of oneof the mounting elements forming a part of the unit;

Figs. 7 and 8 are side and front elevational views, respectively, ofanother of the mounting elements of the unit;

Figs. 9 and 10 are elevation and front views, respectively, of stillanother mounting element of the unit; and

Figs. 11 and 12 are elevation and front views, respectively, of stillanother mounting element of the unit.

In Fig. 1, a typical assembly of a plurality of abrasive units 15 of thepresent invention is illustrated, the units being mounted in spacedend-to-end relation on a common rotatable shaft 16. While the shaft isonly partly shown it will be appreciated that the same is suitablyrotatably driven by a known type of drive arrangement resulting in therotation of the units 15 in the same direction at the same speed.Referring to Figs. 1 and 2, the abrasive element 17 of each of the units15 is in the form of a two-part sleeve including semi-cylindrical sleevesections 18 and 19 of identical construction and mounted to definetherebetween a cylinder received concentrically about the shaft 16.

The abrasive element 17 may be formed by longitudi-.

nallybisecting a length of pipe, such as seamless steel tubing, the pipebeing, of any desired diameter. The. pipe length is sub-divided so as todefine oppositely positioned slots 20 which are preferably of a width ofabout of an;in. h,;thc lo xb ingm intai nc pon mo nt ns the sleevesections 18 'filld 19 in a manner to be described -to, in efiect,provide a slotted cylinder. The outer surface of each sleeve section 18and -19 is coated with a suitable abrasive such as sintered tungstencarbide as disclosed in the aforementioned copending applications. Theinner surfaces at the ends of the sleeve;17 are machined todefine anannular sleeve mounting surface 21 of reduced thickness which terminatesinwardly with a radial annular shoulder 22. The outer surface endmargins of the sleeve 17 are provided with amounting bevel 2 3 and inthis manner the abrasive sleeve 17 is completed and ready-forinstallation.

The sleeve mounting elements of the unit 15, as particularly shownin-Figs. 3 and 4, include'spaced end members 24 and ;25, 'anrabrasivesection end engaging collar 26 and a clampingfring 27. These elementsare illustrated in detail in Figs. 5-12, respectively.

Figs. 5 and 6 illustrate the end member 24 as including an outer axiallyextending hub portion 28 provided with a central bore 29 and beingprovided with an inwardly positioned, enlarged radialportion 30 formounting one end of the abrasive sleeve 17. The inner radial face of theradial portion 30 is provided with an axially projecting shoulder 31 ofreduceddiameter which is aligned with an annular recessed groove 32 ofwedge shape into which the bevel end 23 of the sectionalizedsleeve 17isreceived as shown in Figs. 3 and 4. The inner mounting surface 21 ofthe sleeve 17 is received in engagement with the shoulder 31 of the endmember 24 with the bevel 23 being received within the groove 32. Theinner radial surface of the portion 30, as well as the shoulder 31, areprovided with oppositely positioned, radially inwardly directed drilledopenings 33 into which drive pins 34 are received as shown in Fig. 4.The outer end portions of the drive pins 34 project outwardly of theshoulder 31 and are received within the slots between the side marginsof the sleeve sections 18 and 19. The drive pins 34 are held in sleeveengaging position by set screws 35 advanced into tapped holes 36 whichextend in an axial direction through the radial portion 30 of the endmember 24.

Referring particularly to Fig. 4, the end member 24 is fixed on theshaft 16 by set screws 37 received in radially directed tapped holes inthe axial hubportion 28 thereof and the end member 24 rotates with theshaft. The drive pins 34 rotate with the end member 24 and are held intorque transmitting engagement with the sleeve sections 18 and 19 by thesetscrews 35. Thus, one end of the sleeve 17 is engaged by the endmember 24 for rotation therewith and the shaft 16, the sleeve beingreadily demountable from the end member 24 by axial movement of thesleeve, away from the inner surface thereof to withdraw the beveled endfrom the groove 32 and separate the drive pins 34 from the slots 20.

The end member 25, as particularly shown in Figs. 7 and 8, is formedfrom a series of step-like annular portions 38, 39 and 40 with eachbeing. of progressively greater diameter in an inwardly direction. Thegreatest diameter, however, being such that the end member is readilyreceived within the sleeve 17 upon mounting the same on the shaft 16through its central bore 41 as shown in Fig. 4. The'innermost end or theend member 25 terminates in a radially enlarged shoulder 42 telescopedwithin the sleeve 17 with the outer surface of the portion 40 beingprovided with oppositely positioned slots or grooves 43. The outerperiphery of the intermediate portion 39 is threaded and the outermostportion of least diameter is provided with a plurality of tapped holes44 in which set screws 45 are. received to fix the end member 25 to theshaft 16 for rotation therewith.

Received about the innermost portion 40 of the end member 25 is theabrasive element holding .collar26, the structural details of which areparticularly shown in Figs. 4, 9 and 10. The inner diameter of thecollar 26 is slightly greater than the outer diameter of the portion 40of the end member :25 to allow axial movement of the collar relative tothe end member 25. The collar 26 is provided with an outer, radiallyenlarged portion 46 and an inner, radially reduced portion 47 havingaligned with the outer surface thereof an annular wedge-shaped groove 48into which the remaining bevelled end of the sleeve 17 is received. Theouter surface of the portion 47 is provided with oppositely positioned,radially inwardly directed drilled holes 49 into which drive pins 50 arereceived. The drive pins are held in operative positions by axiallydirected set screws 51 which are introduced into tapped holes 52extending from the outer radial face of the collar 26. As shown in Fig.4, the drive pins 50varc.-of sufiicient length to'hav'e their inner endsreceivedin the oppositely positioned grooves-or slots 43 of the endmember 25 to providea type of spline connection to cause rotation of thecollar 26 with the end member 25 and shaft 16 while allowing axialmovement of the collar 26 relative to the end member 25. The outermostends of the drive pins 50 are received in the slots 20 of the sleeves 17for torque transmission thereto in the same manner as described inconnection with the drive pins 34.

To complete the assembly, the clamping-ring 27, illus trated in detailin Figs. 11 and Y12, is utilized to maintain the collar 26 in mountingand torque transmission engagement with the adjacent end of the sleeve17. The clamping ring 27 is provided with an outer threaded bore 53which communicates with an inner enlarged bore 54. The ring '27 isthreadedly advanced onto the portion 39 of the end member 25 with thethreaded bore 53 being engaged with the threads carried by the outersurface of the portion 39. The inner bore 54 is of sufficient diameterto clear the outer surface of the portion 40 of the end member 25 withthe inner radial face of the ring engaging the outer radial face of the.collar 26. In this manner the ring 27 is threadedly advanced intoengagement with the collar 26 to clamp the same in end support andtorque transmission relationship with the element 17. The ring 27 holdsthe collar 26 against axial movement along the end member 25 and, inaddition, clamps the opposite end of the abrasive element 17 intosupported and torque transmission engagement with the opposite endmember '24.

Following operative mounting of the abrasive element 17 and properclamping of the assembly by advancement of the ring 27, whichadvancement is enhanced for the knurled outer surface thereof, theposition of the ring 27 is fixed by the tightening of set screws 55received in radially inwardly directed tapped holes 56 formed in thering 27 in communication with thebore 53 thereof. In order to protectthe threads formed on the outer surface of the portion 39 of the endmember 25 against the clamping action of the set screws 55, soft metalplug inserts 57 are preferably received within the tapped holes 56 andthe set screws 55 work against these plugs with the latter engaging thethreads of the end members 25.

From the foregoing description of the structural features and operativemounting of the abrasive unit of the present invention, it will beappreciated that the operative length of the unit can be variedconsiderably by merely changing the space between the end members 24and-25. For replacement of an abrasive element, it is necessary merelyto loosen the set screws 55, threadedly retract the clamping rings 27,slidingly retract the holding collar 26 to an extent that the samebecomes disengaged from the adjacent end of the abrasive element 17 andremove the sectionalized abrasive element out of engagement with the endmembers 24 and 25. In this manner the fixed positioning of the endmembers 24 and 25 need not be varied and none of the abrasive elementmounting memhers is removed from the shaft 16. The abrasive element 17can be replaced without disturbing operative mounting of adjacent unitsthus materially reducing the period of inoperativeness of the entireassembly during maintenance of a single unit thereof.

While the foregoing description has been directed to the use of theabrasive unit 15 of the present invention in an assembly wherein aplurality of such units are mounted in spaced relationship on a singleshaft, it will be understood that the important structural features ofthe unit in connection with ready replacement of the abrasive elementthereof can advantageously be utilized in a single unit assembly. Inthis respect, replacement of the abrasive element does not requireactual dismounting of any of the permanent elements from the shaft orspindle carrying the unit. Still further, while the abrasive unit hasparticular utility in leather shaping and processing, it will beappreciated that the same may be used for many different purposes inline with known uses of abrasive units.

Obviously, certain modifications and variations of the invention ashereinbefore set forth may be made without departing from the spirit andscope thereof, and therefore only such limitations should be imposed asare indicated in the appended claims.

I claim:

1. An abrasive unit for mounting on a rotatable shaft, said unitincluding a plurality of arcuate abrasive sleeve sections combined todefine an annular sleeve which is held and drive connected at oppositeends thereof by end members arranged for concentric mounting about ashaft for rotation therewith, one of said end members including anaxially movable sleeve section clamping ring drive connected with saidone end member and holding said sections in operative position spacedrelative to the shaft, and position fixing means for releasably holdingsaid clamping ring in axially advanced position on said one end memberto hold said sections while allowing axial retraction of said clampingring for dismounting of said sections from said end members.

2. An abrasive unit mounted on a rotatable shaft, said unit including aplurality of arcuate abrasive sleeve sections combined to define anannular sleeve concentrically about said shaft and releasably held anddrive connected at opposite ends thereof by end members fixed forrotation with said shaft, one of said end members including an axiallymovable sleeve section clamping ring drive connected 'with said one endmember and holding said sections in operative position spaced relativeto the shaft, and position fixing means for releasably holding saidclamping ring in axially advanced position on said one end member tohold said sections while allowing axial retraction of said clamping ringfor dismounting of said sections from said end members.

3. A plurality of abrasive units mounted on a rotatable shaft in spacedend-to-end relation, each of said units including a plurality of arcuateabrasive sleeve sections combined to define an annular sleeveconcentrically about said shaft and releasably held and drive connectedat opposite ends thereof by end members fixed for rotation with saidshaft, one of said end members including an axially movable sleevesection clamping ring drive connected with said one end member andholding said sections in operative position spaced relative to theshaft, and position fixing means for releasably holding said clampingring in axially advanced position on said one end member to hold saidsections while allowing axial retraction of said clamping ring fordismounting of said sections from said end members independent of theother units on said shaft.

4. An abrasive unit mounted on a rotatable shaft, said unit including apair of substantially semi-cylindrical abrasive sleeve sections mountedconcentrically about said shaft at the ends thereof by end members fixedto said shaft, said sections being spaced from one another along theside margins thereof to define axial slots in which radially directeddrive pins are received, said drive pins being removably carried by saidend members, one of said end members including an axially movable sleevesection clamping ring for holding said sections in operative position,and position fixing means for releasably holding said clamping ring inaxially advanced position on said one end member to hold said sectionswhile allowing axial retraction of said clamping ring for dismounting ofsaid sections from said members.

5. An abrasive unit mounted on a rotatable shaft, said unit including apair of substantially semi-cylindrical abrasive sleeve sections mountedconcentrically about said shaft at the ends thereof by end members fixedto said shaft, said sections being spaced from one another along theside margins thereof to define axial slots in which radially directeddrive pins are received, said drive pins being removably carried by saidend members, the drive pins of one of said end members being received inaxially extending grooves for axial displacement out of said slots fordismounting of said sections and for torque transmission to saidsections while received in said slots, said one end member receivingthereabout an axially movable sleeve section clamping ring for holdingsaid sections and the drive pins in said grooves in operative positions,and position fixing means for releasably holding said clamping ring inaxially advanced position on said one end member to hold said sectionswhile allowing axial retraction of said clamping ring for dismounting ofsaid sections from said end members.

6. An abrasive unit mounted on a rotatable shaft, said unit including apair of substantially semi-cylindrical abrasive sleeve sections mountedconcentrically about said shaft at the ends thereof by end members fixedto said shaft, said section being spaced from one another along the sidemargins thereof to define axial slots in which radially directed drivepins are received, said drive pins being removably carried by said endmembers, one of said end members being of reduced diameter to have theinner end portion thereof telescopically received within said sections,the outer periphery of said one end member having a pair of oppositelypositioned grooves over which an axially slidable section end engagingcollar is received, the driven pins of said one end member being mountedin said collar with the outer ends thereof received in said slots andthe inner ends thereof received in said grooves, an axially movablecollar clamping ring received about said one end member axiallyoutwardly of said collar, and position fixing means forming a part ofsaid clamping ring to releasably hold the same relative to said one endmember in abutment with said collar to engage said collar and said drivepins with said sections.

References Cited in the file of this patent UNITED STATES PATENTS999,436 Dobyne Aug. 1, 1911 2,173,864 Sherman et a1 Sept. 26, 1939

